Abstract: In a wavelength-division-multiplexing optical transmission system in which optical-node apparatuses that perform relay transmission of wavelength-division-multiplexed light are located at specified nodes in a main optical transmission path, an optical amplifier switches level control to constant-gain control when there is a notification of a change in the number of multiplexed wavelengths, and then after a specified amount of time restarts level control so that the level becomes a target level that corresponds to the actual number of wavelengths.

Abstract: A core includes a center core region, a core layer that is formed around the center core region and that has a refractive index lower than that of the center core layer, and at least one buffer core layer that is formed between the center core region and the core layer and that has a refractive index lower than that of the center core region and higher than that of the core layer. A cladding is formed around the core layer and that has a refractive index lower than that of the center core region and higher than that of the core layer. An effective core area at a wavelength of 1550 nm is equal to or smaller than 18 ?m2.

Abstract: A broadband light source device that can generate supercontinuum light in a visible range and having a spectrum with a stable shape and high intensity is provided. The broadband light source device includes a diode-pumped solid-state laser light source that outputs seed light in response to being excited by a laser beam output from a semiconductor laser light source; a wavelength converter that receives the seed light to generate wavelength-converted light having a wavelength different from that of the seed light, and outputs the wavelength-converted light; and a nonlinear medium that receives the wavelength-converted light to generate supercontinuum light having a bandwidth of 100 nm or greater included in a wave band of 400 nm to 700 nm inclusive, and outputs the supercontinuum light.

Abstract: A polarizing film is made of multilayer polarizing fibers embedded within a matrix. The fibers are formed with layers of at least a first and a second polymer material. Layers of the first polymer material are disposed between layers of the second polymer material. At least one of the first and second polymer materials is birefringent. Where the fibers are non-circular in cross-section, the cross-section can be oriented within the polarizer.

Abstract: Techniques for generating terahertz (THz) radiation are provided in which each nonlinear crystal in an array of such crystals is coupled to one or more corresponding waveguides such that any THz radiation generated in any single crystal is coupled into that crystal's THz waveguide structure. After the THz radiation is generated in the crystals and coupled into the waveguides, the individual THz signals may be coherently combined to form a single THz signal (non-coherent configurations are provided as well). Crystal-waveguide arrays embodying the techniques can be used to implement efficient, robust, and compact THz sources suitable for applications such as security screening, medical imaging, quality control and process monitoring in manufacturing operations, and package and container inspection.

Abstract: A waveguide based on a three-dimensional photonic crystal is arranged to provide wave-guiding in a single mode and a mode having a field strength distribution with unimodality in a plane perpendicular to the wave-guiding direction, to thereby enable wave-guiding in a desired frequency band, wherein the three-dimensional photonic crystal has a plurality of line defect members which include a first line defect member made of a medium having a refractive index not smaller than that of the columnar structures and formed in a direction perpendicular to the direction in which the columnar structures extend, and a second line defect member formed in the same direction as the first line defect member.

Abstract: A guiding nonlinearity cell. The novel nonlinearity cell includes a nonlinear medium and a waveguide adapted to guide input electromagnetic energy through the nonlinear medium. In an illustrative embodiment, the cell includes a thin layer of a liquid or solid nonlinear medium disposed between two parallel plates adapted to guide energy through the length of the medium by total internal reflection. The plates can be made from a material having a refractive index less than a refractive index of the medium to provide total internal reflection within the liquid, or they can be made from a material matching the refractive index of the medium such that outer walls of the plates provide total internal reflection, allowing energy to leak into the plates.

Abstract: This device for optically regenerating pulses includes a synchronous intensity modulator to provide time synchronization for pulses passing through it and to stabilize intensity fluctuations in the pulses. In addition, it includes noise suppression circuitry in the form of a saturable absorber that is distinct from the synchronous intensity modulator and the intensity fluctuations stabilizer.

Abstract: An optofluidic device is provided. The device includes a cladding region having a first refractive index, and a channel defined by the cladding region such that the cladding region forms an inner surface or an interface of the channel. The channel is configured to house one or more of a liquid, a solid, a gas, a colloidal, or a suspension sample, wherein the sample has a second refractive index, where the channel is configured to guide radiation, and where the first refractive index is lower than the second refractive index.

Abstract: Techniques, apparatus and systems for providing compensation mechanisms for mode-locked lasers and optical amplifiers and a dispersion compensation mechanism to allow a mode-locked laser and an optical amplifier to be optically coupled to each other and to share a common diffraction grating for a dispersion compensation element for the laser and a separate dispersion compensation element for the amplifier.

Abstract: Optical pulse compressor having a chirp unit including a normal dispersion fiber that provides a positive chirp to an input pulse and having a dispersion compensator including an anomalous fiber is provided. The nonlinear coefficient and the absolute value of the second-order group-velocity dispersion of the anomalous fiber that forms the dispersion compensator is set such that a soliton order becomes one or more, and the fiber length of the anomalous dispersion fiber is made to be equal to or smaller than a length required for optical soliton formation.

Abstract: An optical logic circuit is disclosed. The optical logic circuit is configured on a substrate of a first material. The optical logic circuit also has an optical layer which overlays the substrate layer and is at least partially configured of a second material. The optical layer is patterned to provide a plurality of optical pathways. At least one of the optical pathways transmits an optical bias and at least one optical pathway is configured to provide an optical input and at least one optical pathway is configured to provide an optical output. The optical pathways are configured to provide a Boolean logic output based on the at least one optical input.

Abstract: An optical coupler includes a first optical port, a second optical port, a third optical port, and a fourth optical port. The optical coupler further includes a photonic-bandgap fiber having a cladding, a first core, and a second core. The cladding includes a material with a first refractive index and regions within the cladding. The regions have a second refractive index lower than the first refractive index. The first core is substantially surrounded by the cladding. The first core is optically coupled to the first optical port and to the second optical port. The second core is substantially surrounded by the cladding. The second core is optically coupled to the third optical port and to the fourth optical port. At least a portion of the first core is generally parallel to and spaced from at least a portion of the second core such that the first core is optically coupled to the second core. The first core, the second core, or both the first core and the second core is hollow.

Abstract: An optical fiber delivery system for delivering ultrashort optical pulses that can efficiently transmit high peak power, ultrashort optical pulses from an optical pulse source to a desired position in an optical apparatus is provided. An optical system including such an optical fiber delivery system is also provided. The optical fiber delivery system includes light waveguide means 20 for receiving high-peak power, ultrashort optical pulses and transmitting the optical pulses, negative group-velocity dispersion generation means 30 for providing negative group-velocity dispersion to the optical pulses transmitted through the light waveguide means 20, and an optical fiber 40 that transmits the optical pulses transmitted through the negative group-velocity dispersion generation means 30 along a desired distance. The incident ultrashort optical pulses that have been injected into the light waveguide means 20 are converted into down-chirped pulses.

Abstract: The present invention provides an optical signal noise suppressor and an optical signal noise suppressing method that can decrease noise components to be superimposed on signal light. The optical signal noise suppressor is a device for suppressing noise caused by SBS which is generated when a signal light propagates from a first end side to a second end side of an optical fiber, and comprises a light source section, an optical attenuator, an optical circulator and an optical isolator. A counter light, outputted from the light source section and passing through the optical attenuator, is guided into the optical fiber via the optical circulator. The counter light guided into the optical fiber is interrupted by the optical isolator, and does not reach the signal light source section.

Abstract: A nonlinear optical signal-treating apparatus can suppress the distortion of pulse light to be inputted into an optical fiber to an allowable level or less. The apparatus comprises a pulse light source for outputting first pulse light, a first optical fiber, a second optical fiber that is spliced with the first optical fiber and has a mode-field diameter smaller than that of the first optical fiber, and a light-introducing system for inputting the first pulse light into the first optical fiber. The second optical fiber receives the first pulse light and generates second pulse light having a newly produced wavelength. The peak power ratio of the first pulse light outputted from the first optical fiber to that inputted into the first optical fiber and the pulse width ratio of the first pulse light outputted from the first optical fiber to that inputted into the first optical fiber are 0.5 to 1.5.

Abstract: An all-optical logic gates comprises a nonlinear element such as an optical resonator configured to receive optical input signals, at least one of which is amplitude-modulated to include data. The nonlinear element is configured in relation to the carrier frequency of the optical input signals to perform a logic operation based on the resonant frequency of the nonlinear element in relation to the carrier frequency. Based on the optical input signals, the nonlinear element generates an optical output signal having a binary logic level. A combining medium can be used to combine the optical input signals for discrimination by the nonlinear element to generate the optical output signal. Various embodiments include all-optical AND, NOT, NAND, NOR, OR, XOR, and XNOR gates and memory latch.

Abstract: The present invention relates to an analyzing apparatus and the like having a structure for enabling spectrometry and the like up to a longer frequency region while being excellent in practicality. The analyzing apparatus comprises a light source section and a light-detecting section. The light source section includes a seed light source emitting laser light, and a solid highly nonlinear optical fiber generating SC light in response to the input of the laser light, and thereby emitting the SC light as irradiation light to an object. The light-detecting section detects light to be detected from the object irradiated with the irradiation light. Here, the seed light source in the light source section emits pulsed light having a center wavelength within the range of 1.3 ?m to 1.8 ?m.

Abstract: A surface emission apparatus includes a first light source for emitting invisible light rays; a second light source for emitting visible light rays; a light guide having a light entrance surface for entering therethrough into the light guide the invisible light rays emitted from the first light source and the visible light rays emitted from the second light source, and a light exit surface for emitting the invisible light rays and the visible light rays therethrough out of the light guide; and a plurality of optical devices disposed on a surface of the light guide which confronts the light exit surface, for scattering more of the invisible light rays than the visible light rays.

Abstract: An optical waveguide element includes: an optical waveguide including an organic non-linear optical material; a first electrode arranged on one surface side of the optical waveguide; a second electrode arranged on another surface side of the optical waveguide; a protective member disposed on the second electrode, the protective member including (i) a third electrode which is provided on a first surface of the protective member, the first surface facing the second electrode, the third electrode being electrically connected to the second electrode, (ii) a fourth electrode which is provided on a second surface of the protective member, the second surface opposing the first surface, and (iii) a conductive portion which penetrates through the protective member from the first surface to the second surface, and electrically connects the third electrode and the fourth electrode.

Abstract: In a preferred embodiment, an integrated optical gate matrix, that includes a set of nonlinear elements and waveguides interconnecting at least some nonlinear elements in the set of nonlinear elements, may be configured to enable optical processing. A first subset of the set of nonlinear elements is preferably configured to function as a set of ON/OFF switches in the “OFF” state to enable a second subset of the set of nonlinear elements to be configured in at least one optical processing configuration. Configuration of the second subset of the set of nonlinear elements may be used for various optical processing operations, such as all-optical 2R or 3R regeneration, wavelength conversion, data format conversion, demultiplexing, clock recovery, logic operations and dispersion compensation. Related apparatus and methods are also described.

Abstract: A phase shifter includes at least one photonic crystal structure having alternating high and low index dielectric layers. At least two defect structures are positioned between said photonic crystal structures. The defect structure includes one or more nonlinear materials used to produce an index change, whose effect is amplified to produce a specified phase shift in the output signal of said phase shifter.

Abstract: An elongate waveguide for guiding light including a core having an elongate region of relatively low refractive index; a microstructured region around the core comprising elongate regions of relatively low refractive index interspersed with elongate regions of relatively high refractive index; and a boundary at the interface between the core and the microstructured region, the boundary including, in the transverse cross-section, a region of relatively high refractive index, which is connected to the microstructured region at a plurality of nodes, and at least one relatively enlarged region around the boundary, the enlarged region having a major dimension and a minor dimension, wherein the length of the major dimension divided by the length of the minor dimension is more than 3.0.

Abstract: An optical fiber strain-temperature sensing system includes first and second optical sources respectively generating first and second light signals having different wavelengths. Optical circulators direct the light signals to an external sensing cable for the respective generation of first and second Brillouin scattered light signals. First and second frequency mixers have a first input respectively coupled to the first and second optical light sources. The optical circulators direct the first and second Brillouin scattered light signals respectively to second inputs of the first and second frequency mixers. First and second transducers are respectively coupled to an output of the first and second frequency mixers and are respectively configured for generating first and second electrical signals indicative of a Brillouin frequency shift of the first and second light signals.

Abstract: The present invention relates in general to coupling of light from one or more input waveguides to an output waveguide or output section of a waveguide having other physical dimensions and/or optical properties than the input waveguide or waveguides. The invention relates to an optical component in the form of a photonic crystal fiber for coupling light from one component/system with a given numerical aperture to another component/system with another numerical aperture. The invention further relates to methods of producing the optical component, and articles comprising the optical component, and to the use of the optical component. The invention further relates to an optical component comprising a bundle of input fibers that are tapered and fused together to form an input coupler e.g. for coupling light from several light sources into a single waveguide. The invention still further relates to the control of the spatial extension of a guided mode (e.g.

Abstract: A nonlinear optical signal-treating apparatus can suppress the distortion of pulse light to be inputted into an optical fiber to an allowable level or less. The apparatus comprises a pulse light source for outputting first pulse light, a first optical fiber, a second optical fiber that is spliced with the first optical fiber and has a mode-field diameter smaller than that of the first optical fiber, and a light-introducing system for inputting the first pulse light into the first optical fiber. The second optical fiber receives the first pulse light and generates second pulse light having a newly produced wavelength. The peak power ratio of the first pulse light outputted from the first optical fiber to that inputted into the first optical fiber and the pulse width ratio of the first pulse light outputted from the first optical fiber to that inputted into the first optical fiber are 0.5 to 1.5.

Abstract: An all-optical logic gates comprises a nonlinear element such as an optical resonator configured to receive optical input signals, at least one of which is amplitude-modulated to include data. The nonlinear element is configured in relation to the carrier frequency of the optical input signals to perform a logic operation based on the resonant frequency of the nonlinear element in relation to the carrier frequency. Based on the optical input signals, the nonlinear element generates an optical output signal having a binary logic level. A combining medium can be used to combine the optical input signals for discrimination by the nonlinear element to generate the optical output signal. Various embodiments include all-optical AND, NOT, NAND, NOR, OR, XOR, and XNOR gates and memory latch.

Abstract: A broadband light source includes one or more laser diodes that are capable of generating a pump signal having a wavelength shorter than 2.5 microns, a pulse width of at least 100 picoseconds and a pump optical spectral width. The light source also includes one or more optical amplifiers that are coupled to the pump signal and are capable of amplifying the pump signal to a peak power of at least 500 W. The light source further includes a first fiber that is coupled to the one or more optical amplifiers. The first fiber including an anomalous group-velocity dispersion regime and a modulational instability mechanism that operates to modulate the pump signal. In one particular embodiment, the pump signal wavelength resides in the anomalous group-velocity dispersion regime of the first fiber and where different intensities in the pump signal can cause relative motion between different parts of the modulated pump signal produced through modulational instability in the first fiber.

Abstract: A THz radiation source comprising a dual waveguide heterostructure is provided. The dual waveguide heterostructure includes an optical waveguide contained within a larger THz waveguide layered structure. The radiation source provides a coherent guided wave of THz radiation which is generated via difference frequency mixing in a gain medium with a large second-order nonlinearity and propagated with low THz loss by a dielectric medium in the layered waveguide structure. The THz radiation source is compact, has a high power output, and may be operated in continuous-wave (CW) mode at room temperature.

Abstract: An all-optical logic gates comprises a nonlinear element such as an optical resonator configured to receive optical input signals, at least one of which is amplitude-modulated to include data. The nonlinear element is configured in relation to the carrier frequency of the optical input signals to perform a logic operation based on the resonant frequency of the nonlinear element in relation to the carrier frequency. Based on the optical input signals, the nonlinear element generates an optical output signal having a binary logic level. A combining medium can be used to combine the optical input signals for discrimination by the nonlinear element to generate the optical output signal. Various embodiments include all-optical AND, NOT, NAND, NOR, OR, XOR, and XNOR gates and memory latch.

Abstract: The present invention intends to provide a two-dimensional photonic crystal having a high level of mechanical strength and functioning as a high-efficiency resonator. The two-dimensional photonic crystal according to the present invention includes a slab layer 31 under which a clad layer 32 is located. In the slab layer 31, areas 35 having a refractive index different from that of the slab layer 31 are cyclically arranged to create a two-dimensional photonic crystal. A portion of the cyclic arrangement of the areas 35 are omitted to form a point-like defect 36. This defect 36 functions as a resonator at which a specific wavelength of light resonates. An air-bridge cavity 37 facing the point-like defect 36 is formed over a predetermined range of the clad layer 32. In this construction, the clad layer 32 supports the slab layer 31 except for the range over which the air-bridge space 37 is formed. Therefore, the two-dimensional photonic crystal has a high level of mechanical strength.

Abstract: Polarization-diverse optical devices and related methods are disclosed. In some embodiments, these devices and methods are realized by utilizing a four-port, wavelength-dependent optical coupler that is arranged to receive identical counter-propagating optical signals.

Abstract: A radiation source or detector including a nested waveguide structure is provided. A smaller waveguide provides wave guiding for radiation of shorter wavelength. The smaller waveguide is embedded within a larger waveguide that provides wave guiding for radiation of longer wavelength. Wavelength conversion between the shorter wavelength and the longer wavelength can be realized through a nonlinear process.

Abstract: An optical fiber made of silica-based material includes a core and a cladding formed around the core. The core is doped with germanium dioxide, which increases refractive index and decreases acoustic-wave velocity, and aluminum oxide, which increases both refractive index and acoustic-wave velocity, satisfying ?2.814+0.594×W1?W2?54.100+0.218×W1, W1+W2?60, and W2?56.63?2.04×W1, where W1 is doping amount of germanium dioxide in weight percentage, which is larger than 4.74, and W2 is doping amount of aluminum oxide in weight percentage. A nonlinear coefficient of the optical fiber is equal to or larger than 2.6×10?9W?1.

Abstract: A harmonic generation/beam shaping system to generate a shaped beam having a harmonic relationship with a beam generated by a laser, including a first harmonic generation element and a second harmonic generation element arranged sequentially along an axial beam path extending between an input from the laser and an output of the harmonic generation/beam shaping system and at least two beam shaping elements located along the axial beam path. At least one of the least two beam shaping elements is located between the second harmonic generation element and the laser to transform the beam energy profile into a preferred profile to distribute the beam energy across a larger cross sectional area of at least one harmonic generation element or to reduce peaks in the energy distribution profile of the beam, or both, wherein the preferred profile may be a flat-top profile or a Bessel function profile.

Abstract: A photonic crystal is configured with wavelength converting material to act as a concentrator for electromagnetic energy. The concentrator may also be configured with energy conversion devices to convert the electromagnetic energy into another form of energy.

Abstract: Particular embodiments of the present invention relate generally to semiconductor lasers and wavelength conversion devices and, more particularly, to wavelength conversion devices and methods of fabrication thereof that reduce back reflections of light from the wavelength conversion device to the laser. According to one embodiment of the present invention, a wavelength conversion device comprising a nonlinear optical material is poled with domains comprising randomly varying domain widths defined by an ideal poling period ?I plus or minus a disruption value. According to another embodiment, the wavelength conversion device comprises a plurality of sequentially positioned ideal poling domains and one or more non-ideal poling domains. The ideal poling domains comprise a domain width of the ideal poling period ?I while the non-ideal poling domains comprise a domain width of the ideal poling period ?I plus or minus a discontinuity value.

Abstract: A nonlinear dye-doped polymer optical rectification detector has an optical input for receiving a modulated optical carrier signal, an optical structure for conveying the modulated optical carrier through the detector, and an electrical structure overlaid with the optical structure arranged to optimize matching between electrical and optical waves and to enhance the second order nonlinearity of polymer in the detector. A planar waveguide fabrication method deposits a thin dye-doped polymer film onto a substrate, photobleaches one or more waveguides into the thin dye-doped polymer film, anneals the one or more waveguides to relieve stresses induced during the photobleaching process, and then forms endfaces by cleaving the substrate.

Abstract: Provided herein are photonic devices configured to display photonic band gap structure with a degenerate or a split band edge. Electromagnetic radiation incident upon these photonic devices can be converted into a frozen mode characterized by a significantly increased amplitude, as compared to that of the incident wave. The device can also be configured as a resonance cavity with a giant transmission band edge resonance. In an exemplary embodiment, the photonic device is a periodic layered structure with each unit cell comprising at least two anisotropic layers with misaligned anisotropy. The degenerate or split band edge at a given frequency can be achieved by proper choice of the layers' thicknesses and the misalignment angle. In another embodiment, the photonic device is configured as a waveguide periodically modulated along its axis.

Abstract: A method for preparing a periodically poled structure according to this aspect of the present invention comprises the steps of providing a ferroelectric substrate and performing a poling process by applying a poling current to at least one portion of the ferroelectric substrate according to a current waveform. The current waveform include a major phase and a tailed phase accompanying the major phase; the major phase has at least one peak current (Ip) and terminates when the current drops substantially equal to Ip/e, and the charge delivered to the portion of the ferroelectric substrate during the major phase is larger than that delivered during the tailed phase. The nucleation phase is configured to generate nucleation sites in the portion of the ferroelectric substrate and the spreading phase is configured to increase the size of the nucleation sites.

Abstract: An optical switch, comprising an optical resonator, a first input optical waveguide optically coupled to the optical resonator for guiding a first optical signal to the optical resonator; a second input optical waveguide optically coupled to the optical resonator for guiding a second optical signal to the optical resonator; and an output optical waveguide optically coupled to the optical resonator for guiding a third optical signal from the optical resonator, wherein the optical resonator has a first region and at least one separate second region made of different materials, at least one of which is non-linear to cause different resonance frequencies of the optical resonator for different intensities of light.

Abstract: The present invention includes apparatus and method of a variable step size dithering control algorithm for polarization mode dispersion controllers (PMDCs). The dithering step size of the PCs is adjusted according to the feedback signal including degree of polarization (DOP).

Abstract: An optical fiber device converts an input optical pulse having a predetermined center wavelength into an optical pulse having a wavelength bandwidth broader than that of the input optical pulse. The optical fiber device includes a plurality of optical fibers connected in a cascaded manner each having negative wavelength dispersion at the center wavelength. The optical fibers have different relative refractive index differences between a core region and a cladding region from each other. The optical fibers are connected such that wavelength dispersions of adjacent optical fibers at the center wavelength are different from each other.

Abstract: The present invention provides a method for designing an optical pulse shaper including a first optical propagation line unit having a nonlinear medium and a dispersion medium concatenated, including: specifying design specifications of the first optical propagation line unit; and based on the design specification, calculating a quasi-periodic stationary pulse of which a waveform of an input optical pulse to the first optical propagation line unit is similar to a waveform of an output pulse from the first optical propagation line unit.

Abstract: An image wavelength conversion device for converting an infrared light image into a visible light, a method of manufacturing the device, and an image conversion system using the device are provided. The image wavelength conversion device is formed by an optical waveguide array 3 in which one end and the other end of each of a multitude of quasi-phase-matching sum frequency generating optical waveguides are aligned in a two-dimensional plane. One plane of the optical waveguide array 3 forms an incident plane which includes respective waveguides as elements thereof, and the other plane of the optical waveguide array 3 forms an exit plane which includes waveguides corresponding to the waveguides of the incident plane as elements thereof. From an incident light (?1) and an excitation light (?2) incident to an arbitrary element of the incident plane, an output light (?3) having the relationship of (?1)?1+(?2)?1=(?3)?1 is generated in the corresponding waveguide element.

Abstract: A silicon based source for radiation in the 0.5-14 Terahertz regime. This new class of devices will permit continuously tunable, milli-Watt scale, continuous-wave, room temperature operation, a substantial advance over currently available technologies. The Silicon Terahertz Generator (STG) employs a silicon waveguide for near infrared radiation, situated within a metal waveguide for Terahertz radiation. A nonlinear polymer cladding permits two near-infrared lasers to mix, and through difference frequency generation produces Terahertz output. The small dimensions of the design greatly increase the optical fields, enhancing the nonlinear effect. The design can also be used to detect Terahertz radiation.

Abstract: Provided is an ultra-short pulse light source having an optical pulse generator 111 for emitting short pulse light, an optical amplifier 112 for amplifying the short pulse light output from the optical pulse generator 111 and an optical compressor 120 for compressing the short pulse light. The optical compressor 120 has multi-step configuration of steps polarization beam splitters 1211,2, optical fibers 1221,2, 1231,2 for compressing the incident pulse light, polarization rotating element 1241,2, for rotating the polarization direction of the incident light by 90 degrees to return the light to the optical fibers 1231,2, polarization maintaining optical fibers 1251,2 provided to the output side of the polarization beam splitters 1211,2, and a polarization maintaining optical fiber 1251 at the front step is connected to a polarization maintaining optical fiber 1252 at the rear step.

Abstract: Devices and methods for optical processing and storage are described. In a preferred embodiment, an integrated optical gate matrix, that includes a set of nonlinear elements and waveguides interconnecting at least some nonlinear elements in the set of nonlinear elements, may be configured to enable optical processing. A first subset of the set of nonlinear elements is preferably configured to function as a set of ON/OFF switches in the “OFF” state to enable a second subset of the set of nonlinear elements to be configured in at least one optical processing configuration. Configuration of the second subset of the set of nonlinear elements may be used for various optical processing operations, such as all-optical 2R or 3R regeneration, wavelength conversion, data format conversion, demultiplexing, clock recovery, logic operations and dispersion compensation. Related apparatus and methods are also described.

Abstract: A method for preparing a poled structure comprises the steps of forming a ferroelectric substrate having a top surface and a bottom surface, performing a doping process to form at least one inhibition block in the ferroelectric substrate, forming an electrode structure including a first electrode and a second electrode on the top surface and a third electrode on the bottom surface and applying a predetermined voltage to the electrode structure to form a plurality of inverted domains outside of the inhibition block in the ferroelectric substrate. The ferroelectric substrate has a first polarization direction and a first crystal structure, the inhibition block has a second crystal structure different from the first crystal structure, and the inverted domains have a second polarization direction substantially opposite to the first polarization direction.

Abstract: Method and device for the generation of a comb of stabilized frequency lines and/or a train of ultrashort laser pulses for stabilization of the position of the carrier wave with respect to the amplitude envelope of few cycles laser pulses. Interference between spectral components generated by means of difference frequency generation and self phase modulation in one and the same non-linear crystal (4) allows detecting and stabilizing the temporal evolution of the carrier-envelope offset (CEO) phase. The described technique improves dramatically the accuracy of the stabilization and has very small insertion losses.